package com.sky.aspect;

import com.sky.annotation.AutoFill;
import com.sky.constant.AutoFillConstant;
import com.sky.context.BaseContext;
import com.sky.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.time.LocalDateTime;

/**
 * 自定义切面。实现公共字段自动填充给处理逻辑
 */

@Aspect
@Component
@Slf4j
public class AutoFillAspect {
    /**
     * 切入点
     */

    @Pointcut("execution(* com.sky.mapper.*.*(..)) && @annotation(com.sky.annotation.AutoFill)")
    public void autoFillPointCut(){}


    /**
     * 来一个前置通知,告诉要拦截的通知类型
     *
     */
    @Before("autoFillPointCut()")
    public void autoFill(JoinPoint joinPoint){

        log.info("开始进行公共字段自动填充。。。。");
        //获取要拦截的操作数据类型
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();  //方法签名对象
        AutoFill annotation = signature.getMethod().getAnnotation(AutoFill.class);  //获得方法上的注解对象
        OperationType operationType = annotation.Value(); //获取数据库操作类型


        //获取当前被拦截的方法的参数 --- 实体对象
        Object[] args = joinPoint.getArgs();
        //避免抛出空指针异常
        if (args == null && args.length == 0) {
            return;
        }

        Object entity = args[0];
        //准备赋值的数据
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();
        
        //根据当前不同的操作类型，为对应的属性通过反射来赋值
        if (operationType == OperationType.INSERT){
            //为四个公共字段赋值
            try {
                Method setCreateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
                Method setCreateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

                //通过反射来给对象赋值
                setCreateUser.invoke(entity,currentId);
                setUpdateUser.invoke(entity,currentId);
                setUpdateTime.invoke(entity,now);
                setCreateTime.invoke(entity,now);

            } catch (Exception e) {
                e.printStackTrace();
            }


        } else if (operationType == OperationType.UPDATE) {
            //为两个公共字段赋值

            try {

                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

                //通过反射来给对象赋值

                setUpdateUser.invoke(entity,currentId);
                setUpdateTime.invoke(entity,now);


            } catch (Exception e) {
                e.printStackTrace();
            }


    }


    }


}
